Dust-separator



H. MILLIKEN.

DUST SEPARATOR.

APPLICATION man MAR. I. 1919.

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DUST SEPARA TOR. APPLICATION FILED MAR. I. 1919.

Patented June 22, 1920.

3 SHEETS-SHEET 3,

I Ill/Il INVENTQR W4 Mm ATTORNE UNITED f STATES PATENT" OFFICE-HUMPHREYS MILLIKEN, 0F TENAFLY, NEW JERSEY, ASSIGNOR 0F ONE-HALF TOJOSEPH B. TAYLOR, OF YORK, N. Y.

DUST-SEPARATOR.

Application filed March 1,

To all whom it may concern:

Be it known that I, HUMrHnnYs 'MILLP KEN, a citizen of the UnitedStates, residing at Tenafiy, in the county of Bergen and State of NewJersey, have invented certain new and useful Improvements in Dust-Separators; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same. V

The present invention relates to an improved form of high speed-centrifugal dust separator, especially adapted to extracting orseparating extremely fine dust or fumes from air or gases in which thesame is suspended. 1

In centrifugal separators of this character it is advantageous so totreat the dust-laden gases that the dust may have to travel a minimumradial distance in reaching the surface upon which it is collected,andmay be thereafter conducted outward to the area of delivery with aslittle resistance as possible 'to its progress. It is one of theprincipal objects of the present invention to provide apparatus wherebythese ends may be carried out, either in a vertical or horizontal typeof machine.

Among other objects of the present invention arefthe followingTo providemeans for accelerating and rendering more certain thefeffective travelof dust along the primary collecting surfaces; to provide means forpreventing escape and loss of dust from the clearance space between therotating and the stationary portions of the machine; to provide meansfor the separate collection and delivery of bodies of dust of differentgrades or degrees of fineness and to facilitate final delivery of themasses so collected; to provide a form of mounting for vertical machinesin particular, whereby a limited degree of freedom is given; to therotating portions of the machine, permit-' ting the same to accommodatethemselves to their natural axes of revolution, thereby avoiding strainsupon the bearing. While the means whereby these different objects areattained are all capable of conjoint use upon one and the same machine,this is not"- Specificationof Letters Patent. P t t J 22 1919. SerialNo. 279,930.

essential in all cases, and these various means have therefore beenclaimed herein separately The invention is illustrated in a preferredform in the accompanying drawings, Wherein Figure 1 is a diagrammaticrepresentatlon of the entire device, the rotating member being shown inelevation and the outer stationary casing in section, Fig. 2 is a planview of a segment of the rotating member on an enlarged scale, Fig. 3 isa vertical sectional view of the means for preventing loss of dust atthe joint, Fig. 4 is a similar view of'the driving means for the dustgathering or sweeping device, Fig. 5 is a view partly in elevation andpartly in section showing the sectional mounting employed to permit agyroscopic movement, and F ig. 6 is a fragmentary sectional view takenon theline 6- 6 in Fig. 2.

At 10 is shown the exterior stationary casing, within which is revolublymounted the hollow rotating member within which the centrifugalseparation takes place. This member has conical ends 11 narrowing towardtheir inlet and outlet openings respectively, and the stationary casingis provided with conical extremities 12 and 13 turning inward at theapexes of thecones to form .in-

let and outlet openings respectively, close 'to the inlet and outletopenings ofthe rotary member, but not touching the same. An inlet pipe14 is adapted to convey the dustladen gases to the separator, while apipe 15 at the opposite end receives the gases after separation.

The rotating, or active separating, memher is driven by any suitablemeans, and preferably by theelectric motor 16, which drives the centralshaft 17, and may belocated at either end of the machine. The freeextremity of this shaft is preferably received in a heavy bearing block18 which.

is not secured to. its support. This construction permits a certainamount of gyroscopic movement in the shaft, whichis, at the sametimedamped and limited by the mass of the bearing, and its frictional actionupon its support. 7

The main body of the rotating member comprises a succession of parallelcircular rings 19, of uniform diameter, separated by annular deliveryopenings 20, from which the separated dust is ejected by centrifugalforce, as indicated by the arrows in Fig. 1. These rings 19 aresupported by and rotate with the central shaft, preferably in thefollowing manner.

Upon the shaft 17 is fixed a hub 21, from which radiate the impellingarms or plates 22. These are seen in edge view in Fig. 2, and extendfrom one end to the other of the main rotating body, forming wedgeshaped chambers or spaces which receive the dust-laden gases from thepipe 14:. These plates 22 impel the gases forward and impart to them therotary motion which creates the centrifugal force serving to separatethe dust which they carry.

Upon opposite faces of each impelling plate there are carried outwardlyinclined collecting plates 23, 24, also extending from end to end of themain rotating member,

and arranged in pairs, as shown in Fig. 2.

These plates are preferably slightly bowed outward to lend elasticityand to accommodate them to the centrifugal stresses.

The collecting plates 23 on each impelling plate are preferablymutuallyparallel, and

the same is true of the plates 24L. The outer edges of the collectingplates are bent, as, at and 2(5,so as to unite to form the oppositesides of a radial discharge passage 27 extending through and out of eachwedge shaped space between the impelling plates.

It will be seen that, by this arrangement, the greater part of theinterior of the rotating member is subdivided into secondary chamberslimited by outwardly sloping collecting plates placed a short distanceapart. It follows that the dust carried by' the longitudinal air streamin these secondary chambers is obliged to travel only a relatively shortdistance radially before it is received by the collecting plate on theouter side of such chamber. Here it gathers and forms agglomerationswhose increased mass favors an increased centrifugal eifect, and

this force causes it to slide outward until it reaches a dischargepassage 27, where it is free to join the general stream which is linallydischarged through the annular openings 20.

In order to prevent interference of this travel through the radialdischarge passages 27, it is preferred to provide means toexclude thelongitudinz-il stream of gases from these passages. For this purposeimpedance plates 28 are fastened at intervals (preferably by welding)across the spaces between plates 25, 26. These impedance plates, lyingin transverse radial planes, afford a succession of nearly continuouspartitions across the dischargepassages, and thereby exclude thelongitudinal air stream which would otherwise interfere with prompttravel of the dust along these pasages. The plates 28 also serve tofasten togetherthe opposed plates 25 and 26.

I prefer to support the exterior rings 19 upon the outer ends of thepassages 27 in the manner shown in Figs. 2 and 6. For this purpose theoutermost plates 25 and 26 all around the rotating member are extended.to form tongues 29, which extend into the spaces 20, and the rings 19are held free in the spaces between these tongues. The elasticity of thebowed plates 23 and 24; will facilitate insertion of the rings 19. Thisconstruction has the advantage of allowing the various parts a certaindegree of relative movement in response to the stresses incident tooperation.

It is clear that the coarser particles of dust will be more promptlyexpelled by centrifugal force than the finer ones, and I take advantageof this to so arrange my apparatus that dust of various degrees offineness may be separately collected. For this purpose the outer casingis divided by transverse partitions 31 and 32 preferably having conicalwalls as shown in Fig. 1, thus forming a succession of collectingcompartments 33, 34 and 35. In the outer portion of each compartment Iprefer to locate a movable sweeper, which moves slowly around the sameand sweeps the dust out through the respective discharge tubes 36, 37and 38.

These'sweepers may take various forms, but I prefer to use uprightsweeping plates 100 or scrapers 39, 40 and 41 attached to toothed rings42, 1:3 and 4A, in the respective compartments. These rings are drivenslowly by the pinions 45, 46 and 47 on the shaft 18, driven by anyconvenient means, as by 105 a belt not shown) on the pulley 49. Eachpinion is preferably protected by a housing, as shown. i

In order to promote the rapid and certain travel of the dust along thecollecting sur- 0 faces, and prevent sticking, so far as possible, Iprefer to provide means for imparting vibration to the rotary member,and in the modification shown this takes the form of a pneumatic hammer50 or equiva- 115 lent means for delivering rapid blows upon the end ofthe shaft 17.

In apparatus of this kind there will exist a material tendency for thedust collected near the lower end to escape around the 120 spacenecessarily existing between the lower dge of the rotary member and thestationary part of the machine. In Figs. 1 and 3 is illustrated themeans which I have devised for preventing this escape of dust.

The lower end of the rotary member carries a circular horizontal flange51,- which overlaps the floor of the lowermost compartment 35, andimmediately beneath this flange I place an annular air chamber 52130communicating continuously or at close intervals with the space underthe flange'by an opening or openings 53; Compressed air is supplied tothe chamber 52 by the pipe 54: and this air, escaping by the openings53,flows partly toward the main opening of the machine to join the cleandischarge gases, and partly toward the chamber 35, creating a pressurewhich opposes the tendency of the dust to escape through the joint.

For obtaining the best results, particularly in the separation of veryfine dust, it is desirable to make the rotating member very long inproportion to its diameter. On the other hand, it is found that, wherefreedom of accommodation to gyroscopic motion is given to a rapidlyrotating body, certain unavoidable elements of strain are less seriouslyevident in proportion as the length of rotating body is less, thediameter remaining the same.

In certain cases, therefore, it will be found desirable to divide therotating member of my machine into two or more independent sections, andto give to each the necessary freedom of motion for accommodation tounbalanced forces. In Fig. 5 is illustrated a preferred mode ofconstruction for this purpose.

As there shown, the rotating member is divided into two parts 55 and56,which are separated along the plane 57 a sufficient distance to permitof the small independent motion desirable. The section 55 is carriedupon a hollow shaft 58, and the section 56 is carried upon an innershaft 59, passing axially through the shaft 58. The two shafts arebolted together at one end, as shown, and between them is placed apacking 60 of rubber or other suitable resilient material, which willpermit the necessary small angular displacement between the two shafts.Means for flexibly supporting and driving rotating devices so that theymay accommodate themselves to unbalanced forces are well known in theart, and-any of these may be applied to the combined shafts to drive themachine. F or greater clearness these have been omitted, as they do notform a part of my present invention.

The driving endof this modification, as well as that first described,may be placed either at the bottom .or the top of the machine, asdesired. Other changes may be 7 made by those skilled in the art withoutdeparting from my invention, and I do not limit myself to the detailsherein shown and described.

\Vh at I claim is 1. In a centrifugal dust separator, a rotating memberhaving substantially radial discharge passages and a plurality'ofseparating chambers opening into each passage.

The structure set forth generally in claim ,1 hereof, wherein theseparating chambers areformed by outwardly inclined plates each leadingto a separate opening in the side of the discharge passage.

8. The structure set forth generally in claim 1 hereof, wherein thedischarge palsages are furnished withmeans for preventing longitudinalflow of gases through the same.

4. In a centrifugal dust separator, impelling plates, a dischargepassage located between them, and separating plates carried in pairs onsaid impelling plates and forming chambers opening at intervals into theopposite sides of said discharge passage.

5. The structure set forth generally in claim 4 hereof, wherein thedischarge passage is formed by the outwardly bent edges of theseparating plates.

6. The structure set forth generally in claim 5 hereof wherein theoutwardly bent edges of the separating plates are united by means ofimpedance plates.

7. The structure set forth generally in claim .4: hereof, wherein theseparating plates are bowed and are inclined outwardly from their basesof attachment.

8. In the rotating member of a centrifugal dust separator, exteriorparallel rings with spaces between them, in combination with interiorsupporting members having tongues projecting into said spaces; saidrings lying free between said tongues.

9. The structure set forth generally in claim 8 hereof wherein thesupporting members comprise resilient plates adapted to permitsufiicient displacement to facilitate mounting the exterior ringsbetween the tongues on said plates.

10. In a centrifugal dust separator, an internal rotating body, anexternal casing surrounding the same and divided into compartments atdifferent distances from the inlet end of the machine, and an emptyingpassage for each compartment, in combination with mechanism adapted tosweep the dust in each compartment toward its emptying passage, thesweeping mechanism comprising a scraper in each compartment, :1. toothedring attached thereto, pinions for driving said rings and means fordriving said pinions.

11. In a centrifugal dust separator, a rotating member, a stationarycasing for the same and means for delivering a current of air underpressure around the edge of the rotating member near its discharge end.

12. The structure set forth generally in claim 11 hereof wherein thedischarge end of the rotating member has an annular flange and wherein astationary annular wind chamber is placed parallel to said flange and isprovided with an opening for discharging air under said flange.

13. In a centrifugal dust separator, a rotating member made in twosections placed end to end, and mounting means for said sections adaptedto permit their separate accommodation to independent axes of rev0-lution.

1-1. In a centrifugal dust separator, a r0 tating member made in twosections placed end to end, an innner shaft to which one member isfixed, a hollow shaft surrounding said inner shaft, to which the secondshafts.

tnre.

In testimony whereof, I vaffix: my signa- 15 HUMPHREYS MILLIKEN.

